The present invention relates to .beta.-phellandrene and more particularly to a novel process for its preparation.
.beta.-Phellandrene (1-methylene-4-isopropyl-2-cyclohexene) is widely used in perfumes and artificial essential oils because of its peppery, minty, refreshing, and slightly citrusy odor. Also, .beta.-phellandrene finds importance as an intermediate in various synthesis schemes, such as in the preparation of 1-menthol. However, it has been difficult to synthesize .beta.-phellandrene in good yields, such as from paramenthadienes, because of its ease in isomerizing under most reaction conditions to its .alpha.-phellandrene and .alpha.-terpinene isomers. The present invention provides a method for synthesizing .beta.-phellandrene in good chemical and optical yields.